Verse 184

أَيَّامًا مَّعْدُودَٰتٍ فَمَن كَانَ مِنكُم مَّرِيضًا أَوْ عَلَىٰ سَفَرٍ فَعِدَّةٌ مِّنْ أَيَّامٍ أُخَرَ وَعَلَى ٱلَّذِينَ يُطِيقُونَهُۥ فِدْيَةٌ طَعَامُ مِسْكِينٍ فَمَن تَطَوَّعَ خَيْرًا فَهُوَ خَيْرٌ لَّهُۥ وَأَن تَصُومُوا۟ خَيْرٌ لَّكُمْ إِن كُنتُمْ تَعْلَمُونَ

Specific days. However, if one of you is ill or on a trip, the same number of days shall be substituted later. And it is incumbent upon those who can afford it that they should repay by feeding the poor. Therefore, whoever does any good beyond the call of duty is good for him. And fasting is best for you if you only knew.